The main part of the town extends for a mile along the broad straight Roman road, Watling Street; the high road from Luton to Tring, which crosses it in the centre of the town, representing the ancient Icknield Way.
There may have been a Romano-British village on this site on the Watling Street.
Dunstable (Dunestaple, Donestaple) first appears as a royal borough in the reign of Henry I., who, according to tradition, on account of the depredations of robbers, cleared the forest where Watling Street and the Icknield Way met, and encouraged his subjects to settle there by various grants of privileges.
The Roman Watling Street crossed Shooter's Hill, and a Roman cemetery is supposed to have occupied the site of the Royal Arsenal, numerous Roman urns and fragments of Roman pottery having been dug up in the neighbourhood.
In particular, the Roman "North Road" which ran from York through Corbridge and over Cheviot to Newstead near Melrose, and thence to the Wall of Pius, and which has largely been in use ever since Roman times, is now not unfrequently called Watling Street, though there is no old authority for it and throughout the middle ages the section of the road between the Tyne and the Forth was called Dere Street.